The doctor said jokingly that his own infection of the virus _______ the discovery of a vaccine (疫苗)of the disease.
40. It is obvious that lung diseases are____smoking.
39. As we have known from the map of the world, this is ______.
38. Nowhere else in the world______ cheaper tailoring than in Hong Kong.
37. I tried all I could do ______ the topic at the meeting, but failed.
36. I felt quite ______ when I made my first speech in front of so many people.